These method could be used to enhance numerical stability: neglecting wheelset inertia force acting on bridge, applying iteraion accelerating method and employing larger time step and so on.

• 可采取如下方法改善迭代稳定性：忽略轮对惯性力对桥梁的作用，采用迭代加速技术，选用较大的时间积分步长等。